DAACS staff developed a frequency-seriation based chronology for the Building o site (see Neiman, Galle, and Wheeler 2003 for technical details). DAACS seriated ceramic assemblages, with more than 5 sherds, from individual excavated contexts and from stratigraphic groups -- groups of contexts that field records indicate were part of a single stratigraphic layer or deposit. DAACS assigned such contexts to the same stratigraphic group. Stratigraphic groups have a SG-prefix, which precedes the group number (e.g. SG01 equals Stratigraphic Group 1). Not all contexts have stratigraphic group assignments.

DAACS chose to base its seriation chronology for the North Hill Site on ceramic assemblages aggregated at the level of stratigraphic groups and unassigned contexts, and not at the level of features. Only four features (F06, F16, F24, F25) contained more than five ceramic shreds. Frequencies of MCD-types in these four assemblages betrayed no convincing temporal structure.

DAACS computed the frequency of MCD-types in stratigraphic groups and unassigned contexts. The seriation chronology is derived from a correspondence analysis of these frequencies. Seriated assemblages were assigned to phases. Phases are groups of assemblages that have similar correspondence-analysis scores and are therefore inferred to be broadly contemporary. Phases assigned by DAACS have a P-prefix that precedes the phase number (e.g. P01 equals Phase 1).

The stratigraphic relationships among stratigraphic groups and unassigned contexts are summarized in the Harris Matrix for the site. Phase assignments from the seriation are shown on the Harris Matrix in color, facilitating comparison of the seriation chronology and the stratigraphic chronology of the site.

Based on the correspondence analysis, DAACS assigned the ceramic assemblages to one of three phases. Mean ceramic dates for the phases are given in the table below. The table also includes two estimates of the TPQ for each phase. The first TPQ estimate is the usual one – the maximum beginning manufacturing date among all the MCD-types in the assemblage. The second estimate -- TPQp90 -- is the 90th percentile of the beginning manufacturing dates among all the shreds in the assemblage, based on their MCD-types. This TPQ estimate is more robust against excavation errors and taphonomic processes that might have introduces a few anomalously late sherds in an assemblage.

In contrast to the Poplar Forest Quarter Site, the temporal patterning among assemblages from stratigraphic groups and contexts is strong and temporal distinctions among all three phases seem significant. In addition the Harris matrix reveals a strong correlation between the seriation order of the assemblages and the stratigraphic order of the deposits from which they were derived.

Click on the following link to access a seriation chronology for the North Hill Site. We use the indefinite article to signify that it is not the only chronology possible, nor even the best one possible.